CN115071944A - Diesel engine vibration damping base based on acoustic black hole nonlinear contact - Google Patents

Abstract

The invention discloses a diesel engine vibration damping base based on acoustic black hole nonlinear contact, which comprises a base top plate, a base bottom plate, a bearing beam and an acoustic black hole structure, wherein the base top plate is provided with a plurality of through holes; the bearing beam is arranged between the base top plate and the base bottom plate; at least one bearing beam is arranged between the base top plate and the base bottom plate; at least one bearing beam is connected with an acoustic black hole structure, and the acoustic black hole structure is respectively parallel to the base top plate and the base bottom plate; a conical contact structure is arranged on the base bottom plate and is arranged below the acoustic black hole structure; the conical contact structure and the acoustic black hole are in nonlinear contact. According to the invention, the bearing beam is provided with the acoustic black hole structure, so that vibration generated during the operation of the diesel engine is transferred to the acoustic black hole structure for damping; the acoustic black hole structure is in nonlinear contact with the conical contact structure, low-frequency energy on the acoustic black hole structure is converted into high-frequency energy, the frequency of the original vibration wave is changed, and the vibration reduction speed and effect are improved.

Description

A Diesel Engine Vibration Reduction Base Based on Nonlinear Contact of Acoustic Black Holes

technical field

The invention belongs to the technical field of vibration damping devices for diesel engine bases, in particular to a diesel engine vibration damping base based on nonlinear contact of acoustic black holes.

Background technique

As the main power equipment of ships, diesel engines often cause complex vibration disturbances to ships during the working process, which affects the safety, stability and mechanical performance of ships, and can easily lead to physical discomfort for people on board. As a kind of acoustic wave control technology with simple structure and high vibration damping efficiency, acoustic black hole can be designed according to the thickness of the structure and realize energy accumulation through a certain cut, so that damping materials can be pasted in the vibration energy accumulation area to realize low-cost and high-efficiency acoustic energy. consume. However, the acoustic black hole has a cut-off frequency, and when the cut-off frequency is lower than the cut-off frequency, the vibration reduction effect of the acoustic black hole will be invalid.

Disclosed in Chinese patent (application number: 202010635526.2, application publication number: CN 113879459 A) a composite wave blocking base of hull based on acoustic black hole effect, the composite wave blocking base of hull comprises: a base panel; a base a base plate; a base web, which is located between the base panel and the base base plate; a base bracket, the base bracket is configured to be perpendicular to the base panel, The base bottom plate and the base web; wherein, the base web and/or the base bracket are provided with a plurality of acoustic black hole structures, and the plurality of the acoustic black hole structures are in at least three straight lines Arrangement, the acoustic black hole structures on any two adjacent straight lines are periodically arranged with different arrangement rules.

Referring to the Chinese patent disclosed above, a hull composite wave blocking base based on the acoustic black hole effect still has the following shortcomings: only through the acoustic black hole structure, the vibration reduction function cannot be effectively realized, and it can only play an auxiliary role to make the vibration reduction effect. not good.

SUMMARY OF THE INVENTION

Aiming at the above shortcomings, the present invention provides a diesel engine vibration damping base based on the nonlinear contact of acoustic black holes, which is simple in structure, convenient in use and good in damping effect.

The purpose of the present invention is to realize in this way: a kind of diesel engine vibration damping base based on acoustic black hole nonlinear contact, the vibration damping base is connected with the diesel engine through a connecting mechanism; it is characterized in that: the vibration damping base comprises: The base top plate, the base bottom plate, the load-bearing beam and the acoustic black hole structure; the load-bearing beam is arranged between the base top plate and the base bottom plate;

At least one load-bearing beam is arranged between the base top plate and the base bottom plate;

The at least one load-bearing beam is constructed with an acoustic black hole structure, and the acoustic black hole structure is parallel to the base top plate and the base bottom plate respectively;

The base plate is provided with a conical contact structure, and the conical contact structure is arranged below the acoustic black hole structure; the conical contact structure and the acoustic black hole structure make contact when they collide.

Preferably, the acoustic black hole structure includes an acoustic black hole beam and an acoustic black hole wedge surface, and the acoustic black hole beam adopts a square structure; one end of the acoustic black hole beam is connected to the load-bearing beam, and the other end is connected to the acoustic black hole wedge surface.

Preferably, the conical contact structure is arranged below the acoustic black hole beam; the conical contact structure and the acoustic black hole beam make contact when they collide; let x ₀ be the distance between the conical collision structure and the connection between the acoustic black hole beam and the load-bearing beam distance; x ₁ is the length of the acoustic black hole beam; then the specific position of the conical collision structure satisfies x ₀ <x ₁ .

Preferably, the relationship between the acoustic black hole beam and the acoustic black hole wedge surface is as follows:

h₀为声学黑洞楔面的末端厚度；h₁为声学黑洞楔面的前端厚度；x₁为声学黑洞梁的长度；x₂为声学黑洞结构的总长度。in,

h ₀ is the end thickness of the acoustic black hole wedge; h ₁ is the front end thickness of the acoustic black hole wedge; x ₁ is the length of the acoustic black hole beam; x ₂ is the total length of the acoustic black hole structure.

Preferably, the bottom of the base plate is connected to the ship shell, and the base bottom plate and the ship shell are fixedly connected.

Preferably, the damping coating adopts high molecular polymer or asphalt.

The thickness of the damping coating is 0.8-1.5 times the minimum thickness of the wedge surface of the acoustic black hole.

Preferably, a concave space is provided on the acoustic black hole beam. The acoustic black hole beam is provided with a concave space to reduce the weight of the acoustic black hole beam, so as to increase the range of nonlinear contact caused by structural vibration, thereby improving the vibration reduction effect.

Preferably, the vibration damping base includes a base top plate and a base bottom plate, five load-bearing beams are evenly constructed between the base top plate and the base bottom plate, and three acoustic beams are evenly constructed on the four load-bearing beams arranged in sequence A black hole structure; a conical contact structure is arranged on the base bottom plate, and the conical contact structure is arranged below the acoustic black hole structure; a conical contact structure is arranged below the acoustic black hole structure; Contact occurs when acoustic black hole structures collide.

The beneficial effects of the present invention are as follows: 1. By setting the acoustic black hole structure on the load-bearing beam, the vibration generated by the diesel engine during operation is transferred to the acoustic black hole structure for shock absorption; at the same time, a conical contact structure is connected below the acoustic black hole structure, and the acoustic black hole The structure converts the low-frequency energy on the acoustic black hole structure into high-frequency energy through nonlinear contact with the conical contact structure, changes the frequency of the original vibration wave, improves the speed and effect of vibration reduction, and completes noise reduction.

2. By setting a concave space on the upper end face of the acoustic black hole beam, the change of the vibration wave can be changed to realize the wave gathering; at the same time, the energy can be gathered by the acoustic black hole wedge surface, and the gathered energy can be gathered by the damping coating provided on the acoustic black hole wedge surface. High-frequency energy consumption further accelerates the energy attenuation effect and effectively improves the overall vibration reduction performance.

Description of drawings

FIG. 1 is an overall structural diagram of the present invention.

FIG. 2 is a schematic diagram of a part of the structure of the present invention.

FIG. 3 is a schematic diagram of a part of the structure of the present invention.

FIG. 4 is a front view of the present invention.

Figure 5 is an enlarged view of A.

Figure 6 is a schematic diagram of acoustic black hole parameters.

Among them, 1 diesel engine, 2 base top plate, 3 load-bearing beam, 4 base bottom plate, 5 acoustic black hole beam, 6 acoustic black hole wedge surface, 7 ship shell, 8 conical contact structure.

Detailed ways

The present invention is further outlined below in conjunction with the accompanying drawings.

As shown in Figures 1, 2, and 3, a vibration-damping base for a diesel engine 1 based on the nonlinear contact of acoustic black holes includes a base top plate 2, a base bottom plate 4, a load-bearing beam 3 and an acoustic black hole structure; the load-bearing beam 3 is located in the Between the base top plate 2 and the base bottom plate 4, the two ends of the load-bearing beam 3 are vertically connected to the base top plate 2 and the base bottom plate 4 respectively; between the base top plate 2 and the base bottom plate 4, a plurality of load-bearing beams 3 are evenly arranged The acoustic black hole structure includes an acoustic black hole beam 5 and an acoustic black hole wedge surface 6, one end of the acoustic black hole beam 5 is connected to the load-bearing beam 3, and the other end is connected to the acoustic black hole wedge surface 6; the acoustic black hole beam 5 is vertically connected to the load-bearing beam 3, and the acoustic black hole beam 5 is parallel to the base top plate 2 and the base bottom plate 4; a plurality of acoustic black hole beams 5 are evenly arranged on the load-bearing beam 3.

Further, as shown in Fig. 6, the other end of the acoustic black hole beam 5 is connected to the acoustic black hole wedge surface 6, and the relationship between the main parameters of the acoustic black hole beam 5 and the acoustic black hole wedge surface 6 is as follows:

h₀为声学黑洞楔面6的末端厚度；h₁为声学黑洞楔面6的前端厚度；x₁为声学黑洞梁5的长度；x₂为声学黑洞结构的总长度。in,

h ₀ is the end thickness of the acoustic black hole wedge 6; h ₁ is the front end thickness of the acoustic black hole wedge 6; x ₁ is the length of the acoustic black hole beam 5; x ₂ is the total length of the acoustic black hole structure.

Further, as shown in FIG. 4 , the base bottom plate 4 is provided with a conical contact structure 8, and the conical contact structure 8 is arranged below the acoustic black hole beam 5 and is non-linearly connected with the acoustic black hole beam 5; let x ₀ be the cone The distance from the collision structure to the connection between the acoustic black hole beam 5 and the load-bearing beam 3; x ₁ is the length of the acoustic black hole beam 5; then the specific position of the cone collision structure satisfies x ₀ <x ₁ , and the acoustic black hole beam 5 collides with the cone Each time the structure is in contact, a certain amount of energy is sputtered from the low-frequency region to the high-frequency region, so that the energy of the system is redistributed in the frequency domain.

Further, as shown in FIG. 5 , the acoustic black hole beam 5 is provided with a concave space, and the weight of the acoustic black hole beam 5 is reduced to increase the range of nonlinear contact caused by structural vibration; the upper surface of the acoustic black hole wedge surface 6 is provided with damping. For the coating, the damping coating can be made of high molecular polymer or asphalt; the thickness of the damping coating is 0.8 to 1.5 times the minimum thickness of the acoustic black hole wedge surface 6 .

Example:

The overall dimensions of the base of the diesel engine 1 are selected to be 0.5m long, 0.4m wide and 0.05m high, and the acoustic black hole structure dimensions x ₀ =0.025m, h ₁ =0.003m, and x ₂ =0.04m.

As shown in Figures 1 and 2, the entire diesel engine 1 vibration damping base adopts two base top plates 2 and one base bottom plate 4, and the two base top plates 2 are respectively connected to the two sides of the base bottom plate 4 through load-bearing beams 3 , 5 load-bearing beams 3 are evenly arranged between the base top plate 2 and the base bottom plate 4, and the first four load-bearing beams 3 arranged in order from left to right are evenly arranged with 3 acoustic black hole structures. The nonlinear connection has a conical contact structure 8 .

As shown in FIG. 3 , the base bottom plate 4 is fixedly connected to the ship hull 7 , and the diesel engine 1 is connected to the base top plate 2 through bolts to realize detachable connection.

As shown in Figures 4 and 5, the acoustic black hole structure includes an acoustic black hole beam 5 and an acoustic black hole wedge surface 6. One end of the acoustic black hole beam 5 is connected to the load-bearing beam 3, and the other end is connected to the acoustic black hole wedge surface 6; the acoustic black hole beam 5 is vertically connected to the load-bearing beam 3. On the beam 3, the acoustic black hole beam 5 is parallel to the base top plate 2 and the base bottom plate 4; the other end of the acoustic black hole beam 5 is connected to the acoustic black hole wedge surface 6, and the product of the exponential function and the power function is used to represent the acoustic black hole beam 5 and the acoustic black hole. The main parameter relationship of the black hole wedge surface 6, the main parameter relationship is as follows:

h₀为声学黑洞楔面6的末端厚度；h₁为声学黑洞楔面6的前端厚度；x₁为声学黑洞梁5的长度；x₂为声学黑洞结构的总长度。在声学黑洞梁5的下方设置锥型碰撞结构，锥型碰撞结构的底面连接在基座底板4上，设x₀为锥形碰撞结构到声学黑洞梁5与承重梁3连接处的距离；x₁为声学黑洞梁5的长度；则锥形碰撞结构的具体位置满足x₀＜x₁，声学黑洞梁5与锥形碰撞结构每接触一次，均有一定量的能量从低频区内溅射到高频区，从而使系统的能量在频域内得到重新分布。in,

h ₀ is the end thickness of the acoustic black hole wedge 6; h ₁ is the front end thickness of the acoustic black hole wedge 6; x ₁ is the length of the acoustic black hole beam 5; x ₂ is the total length of the acoustic black hole structure. A cone-shaped collision structure is arranged below the acoustic black hole beam 5, and the bottom surface of the cone-shaped collision structure is connected to the base bottom plate 4, and x ₀ is the distance from the cone collision structure to the connection between the acoustic black hole beam 5 and the load-bearing beam 3; x ₁ is the length of the acoustic black hole beam 5; then the specific position of the conical collision structure satisfies x ₀ <x ₁ , every time the acoustic black hole beam 5 contacts the conical collision structure, a certain amount of energy is sputtered from the low frequency region to the high level. frequency domain, so that the energy of the system is redistributed in the frequency domain.

The upper surface of the acoustic black hole wedge surface 6 is provided with a damping coating, and the damping coating material is high molecular polymer or asphalt, and the thickness of the damping coating is 0.8-1.5 times of the minimum thickness of the acoustic black hole wedge surface 6 .

Working principle: Diesel engine 1 is the main power equipment of the ship. Diesel engine 1 generates complex vibrations and acts on the base roof 2 during operation. The base roof 2 transmits the vibration energy through the load-bearing beam 3 to the acoustic black hole beam 5, and the acoustic black hole beam 5 During the vibration process, it contacts with the cone-shaped collision structure on the base bottom 8 to generate collision, and by means of the nonlinear principle of contact, the low-frequency energy is converted into high-frequency energy. At the same time, based on the energy gathering effect of the acoustic black hole wedge surface 6, the damping coating consumes the high frequency energy that has been accumulated on the black hole wedge surface, so as to complete the vibration isolation and noise reduction of the base during the working process of the diesel engine 1.

The above descriptions are merely embodiments of the present invention, and are not intended to limit the present invention. Various modifications and variations of the present invention are possible for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims (10)

1. a diesel engine (1) vibration damping base based on acoustic black hole nonlinear contact, described this vibration damping base is connected with diesel engine (1) by connecting mechanism; It is characterized in that: described this vibration damping base comprises a base. a seat top plate (2), a base bottom plate (4), a load-bearing beam (3) and an acoustic black hole structure; The load-bearing beam (3) is arranged between the base top plate (2) and the base bottom plate (4); At least one load-bearing beam (3) is arranged between the base top plate (2) and the base bottom plate (4); The at least one load-bearing beam (3) is constructed with an acoustic black hole structure, and the acoustic black hole structure is respectively parallel to the base top plate (2) and the base bottom plate (4); The base bottom plate (4) is provided with a conical contact structure (8), and the conical contact structure (8) is arranged below the acoustic black hole structure; when the conical contact structure (8) collides with the acoustic black hole structure, the touch. 2. a kind of diesel engine vibration damping base based on acoustic black hole nonlinear contact according to claim 1, is characterized in that: described acoustic black hole structure comprises acoustic black hole beam (5) and acoustic black hole wedge surface (6), acoustic The black hole beam (5) adopts a square structure; one end of the acoustic black hole beam (5) is connected to the load-bearing beam (3), and the other end is connected to the acoustic black hole wedge surface (6). 3. a kind of diesel engine vibration damping base based on acoustic black hole nonlinear contact according to claim 2, is characterized in that: described conical contact structure (8) is arranged below acoustic black hole beam (5); Contact occurs when the shaped contact structure (8) collides with the acoustic black hole beam (5); let x ₀ be the distance from the conical collision structure to the connection between the acoustic black hole beam (5) and the load-bearing beam (3); x ₁ is the acoustic black hole The length of the beam (5); then the specific position of the conical collision structure satisfies x ₀ <x ₁ . 4. A diesel engine vibration damping base based on nonlinear contact of acoustic black holes according to claim 2, characterized in that: the upper surface of the acoustic black hole wedge surface (6) is provided with a damping coating. 5 . The vibration damping base of a diesel engine based on nonlinear contact of acoustic black holes according to claim 2 , wherein a concave space is provided on the acoustic black hole beam ( 5 ). 6 . 6. a kind of diesel engine vibration damping base based on acoustic black hole nonlinear contact according to claim 2, is characterized in that: the relation between described acoustic black hole beam (5) and acoustic black hole wedge surface (6) is as follows:

in,

h ₀ is the end thickness of the acoustic black hole wedge surface (6); h ₁ is the front end thickness of the acoustic black hole wedge surface (6); x ₁ is the length of the acoustic black hole beam (5); x ₂ is the total length of the acoustic black hole structure. 7. A kind of diesel engine vibration damping base based on acoustic black hole nonlinear contact according to claim 1, it is characterized in that: the bottom of the base bottom plate (4) is connected to the ship hull (7), the base bottom plate (4) ) and the ship shell (7) are fixedly connected. 8 . The vibration damping base of a diesel engine based on nonlinear contact of acoustic black holes according to claim 4 , wherein the damping coating is made of high molecular polymer or asphalt. 9 . 9. A diesel engine vibration damping base based on nonlinear contact of acoustic black holes according to claim 4, characterized in that: the thickness of the damping coating is 0.8 to 1.5 times the minimum thickness of the acoustic black hole wedge surface (6) . 10. The diesel engine vibration damping base of the acoustic black hole nonlinear contact according to any one of claims 1-9, wherein the vibration damping base comprises a base top plate (2) and a base bottom plate (4) ), five load-bearing beams (3) are uniformly constructed between the base top plate (2) and the base bottom plate (4), and three acoustic black hole structures are uniformly constructed on the four load-bearing beams (3) arranged in sequence.

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